A senior Chinese official, who described the South Korea-U.S. military alliance as a ``historical relic,'' is being accused of diplomatic insensitivity.

Chinese diplomatic officials Wednesday offered an explanation for what they called a ``spontaneous comment,'' by their spokesman. But observers say the incident reflects China's uneasiness over President Lee Myung-bak's effort to foster a strong alliance with the United States.

China's foreign ministry spokesman Qin Gang reportedly made the controversial comment at a press briefing Tuesday, the day when President Lee Myung-bak arrived in Beijing to begin his four-day official visit.

According to the spokesman, ``the Korean-U.S. alliance is a historical relic. The times have changed and Northeast Asian countries are going through many changes and transformations. We should not approach current security issues with military alliances left over from the past Cold War era.''

Officials from Korea's Ministry of Foreign Affairs and Trade were reportedly caught off guard by the comment Tuesday and had made an inquiry to their Chinese counterparts.

``When we asked China's Foreign Ministry about the comment, they said what they really meant was that the alliance had developed through a historical process. They said there was no intention to criticize the alliance,'' a foreign ministry official told reporters. Currently, there are some 28,000 U.S. troops stationed in South Korea.

Chinese diplomats also explained Qin's comment about the alliance being a product of the Cold War era and unfit to tackle the current regional issues. ``The Chinese officials told us that China has always acknowledged the constructive role played by the South Korea-U.S. alliance,'' the official said.

President Lee's pro-American approach has been criticized in China, with some Chinese academics speaking about the potential U.S. effort to weaken China's diplomatic relations.

President Lee is on the third day of his four-day visit to China. On Tuesday, President Lee and Chinese President Hu Jintao agreed to raise the South Korea-China relationship to ``a strategic partnership,'' an upgrade from ``a partnership of comprehensive cooperation'' under the Roh Moo-hyun administration.